Fatigue

Fatigueortirednessis aphysicalormentalfeeling. It happens when someone is ready tosleepor has done a lot of physicalexercise.The person may feel weak, slow or sleepy. They mayyawnand may find it difficult to keep theeyesopen. Usual fatigue goes away when yourestor sleep.

Fatigue may also be caused byphysicalormental illness,jet lag,drugoralcoholuse,medications,blood loss,malnutrition,starvation,stressorboredom.

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v t e Mental processes
Cognition	Consciousness Critical thinking Decision-making Imagination Problem solving Awareness Comprehension Intuition
Perception	Color RGB model Peripheral Visual Haptic(Touch) Sound Harmonics Pitch Speech Amodal Depth Form Perception as interpretation Social seeSociety ASMR
Memory	Consolidation Encoding Storage Recall
Other	Attention Learning Mental fatigue Thinking Higher nervous activity Intention Mental set Volition